I remember we were doing an improv exercise at college where we had to pretend we were in the big brother house. The tutor played the part of the “big brother” character and he basically told us the situations and the rules for the improv. At some point he told us that the house was being locked down and we would be poisoned to death with Chlorine gas for the entertainment of the viewers. We all started pretending to be freaked out and getting upset. Then we all actually started getting freaked out and upset. People started screaming and crying. At one point I picked up a chair and threw it at the window, which luckily did not break. We were all so completely absorbed in the game that even though we knew it wasn’t real, we were allowing ourselves to go so far as to behave as though it was. Then the room started to fill with gas and we started running out of air. We collapsed one by one and passed out. Some people actually passed out. Then the tutor told us that it had been a test and there was no gas. We were all free to leave. He walked out of the room and we were just supposed to carry on with the day. This had been an exercise just like any other and now we were supposed to just carry on.
Looking back on it now I think it was kind of pointless. It’s an interesting story though.